Fig. REF  presents the performance of different \((1944, 972)\)  polar codes. It can be observed that the polar subcode with \(K_{18} \otimes F_{2} \otimes K_{27}\)  polarizing transform under SCL decoding with \(L = 4\)  provides significant performance gain compared to MK polar subcode with \(F_3 \otimes T_3^{\otimes 5}\)  polarizing transform and hybrid design with 8-bit CRC [1]}. Moreover, \(K_{18} \otimes F_{2} \otimes K_{27}\)  polar subcode with \(L = 8\)  has the same performance as shortened polar subcode decoded with \(L = 16\) .
